bnxt_en: support lane configuration via ethtool

Recent kernels support changing the number of link lanes via ethtool.
This is useful for determining the appropriate signal mode to use when
a given link speed can be achieved using different lane configurations.

Accept the ethtool lanes parameter when configuring forced speed.  If
there is no lanes parameter, select a default.

Signed-off-by: Edwin Peer <edwin.peer@broadcom.com>
Signed-off-by: Michael Chan <michael.chan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt_ethtool.c b/drivers/net/ethernet/broadcom/bnxt/bnxt_ethtool.c
index c925e21eadec88f299b613e25e91a7398df28e1f..19b0bff9c590849ad22fe26f1302c31cd7c5b7db 100644 (file)
--- a/drivers/net/ethernet/broadcom/bnxt/bnxt_ethtool.c
+++ b/drivers/net/ethernet/broadcom/bnxt/bnxt_ethtool.c
@@ -2019,13 +2019,15 @@ static int bnxt_get_link_ksettings(struct net_device *dev,
        return 0;
 }
 
-static int bnxt_force_link_speed(struct net_device *dev, u32 ethtool_speed)
+static int
+bnxt_force_link_speed(struct net_device *dev, u32 ethtool_speed, u32 lanes)
 {
        struct bnxt *bp = netdev_priv(dev);
        struct bnxt_link_info *link_info = &bp->link_info;
        u16 support_pam4_spds = link_info->support_pam4_speeds;
        u16 support_spds = link_info->support_speeds;
        u8 sig_mode = BNXT_SIG_MODE_NRZ;
+       u32 lanes_needed = 1;
        u16 fw_speed = 0;
 
        switch (ethtool_speed) {
@@ -2046,37 +2048,46 @@ static int bnxt_force_link_speed(struct net_device *dev, u32 ethtool_speed)
                        fw_speed = PORT_PHY_CFG_REQ_FORCE_LINK_SPEED_10GB;
                break;
        case SPEED_20000:
-               if (support_spds & BNXT_LINK_SPEED_MSK_20GB)
+               if (support_spds & BNXT_LINK_SPEED_MSK_20GB) {
                        fw_speed = PORT_PHY_CFG_REQ_FORCE_LINK_SPEED_20GB;
+                       lanes_needed = 2;
+               }
                break;
        case SPEED_25000:
                if (support_spds & BNXT_LINK_SPEED_MSK_25GB)
                        fw_speed = PORT_PHY_CFG_REQ_FORCE_LINK_SPEED_25GB;
                break;
        case SPEED_40000:
-               if (support_spds & BNXT_LINK_SPEED_MSK_40GB)
+               if (support_spds & BNXT_LINK_SPEED_MSK_40GB) {
                        fw_speed = PORT_PHY_CFG_REQ_FORCE_LINK_SPEED_40GB;
+                       lanes_needed = 4;
+               }
                break;
        case SPEED_50000:
-               if (support_spds & BNXT_LINK_SPEED_MSK_50GB) {
+               if ((support_spds & BNXT_LINK_SPEED_MSK_50GB) && lanes != 1) {
                        fw_speed = PORT_PHY_CFG_REQ_FORCE_LINK_SPEED_50GB;
+                       lanes_needed = 2;
                } else if (support_pam4_spds & BNXT_LINK_PAM4_SPEED_MSK_50GB) {
                        fw_speed = PORT_PHY_CFG_REQ_FORCE_PAM4_LINK_SPEED_50GB;
                        sig_mode = BNXT_SIG_MODE_PAM4;
                }
                break;
        case SPEED_100000:
-               if (support_spds & BNXT_LINK_SPEED_MSK_100GB) {
+               if ((support_spds & BNXT_LINK_SPEED_MSK_100GB) &&
+                   lanes != 2 && lanes != 1) {
                        fw_speed = PORT_PHY_CFG_REQ_FORCE_LINK_SPEED_100GB;
+                       lanes_needed = 4;
                } else if (support_pam4_spds & BNXT_LINK_PAM4_SPEED_MSK_100GB) {
                        fw_speed = PORT_PHY_CFG_REQ_FORCE_PAM4_LINK_SPEED_100GB;
                        sig_mode = BNXT_SIG_MODE_PAM4;
+                       lanes_needed = 2;
                }
                break;
        case SPEED_200000:
                if (support_pam4_spds & BNXT_LINK_PAM4_SPEED_MSK_200GB) {
                        fw_speed = PORT_PHY_CFG_REQ_FORCE_PAM4_LINK_SPEED_200GB;
                        sig_mode = BNXT_SIG_MODE_PAM4;
+                       lanes_needed = 4;
                }
                break;
        }
@@ -2086,6 +2097,11 @@ static int bnxt_force_link_speed(struct net_device *dev, u32 ethtool_speed)
                return -EINVAL;
        }
 
+       if (lanes && lanes != lanes_needed) {
+               netdev_err(dev, "unsupported number of lanes for speed\n");
+               return -EINVAL;
+       }
+
        if (link_info->req_link_speed == fw_speed &&
            link_info->req_signal_mode == sig_mode &&
            link_info->autoneg == 0)
@@ -2130,7 +2146,7 @@ static int bnxt_set_link_ksettings(struct net_device *dev,
        struct bnxt_link_info *link_info = &bp->link_info;
        const struct ethtool_link_settings *base = &lk_ksettings->base;
        bool set_pause = false;
-       u32 speed;
+       u32 speed, lanes = 0;
        int rc = 0;
 
        if (!BNXT_PHY_CFG_ABLE(bp))
@@ -2171,7 +2187,8 @@ static int bnxt_set_link_ksettings(struct net_device *dev,
                        goto set_setting_exit;
                }
                speed = base->speed;
-               rc = bnxt_force_link_speed(dev, speed);
+               lanes = lk_ksettings->lanes;
+               rc = bnxt_force_link_speed(dev, speed, lanes);
                if (rc) {
                        if (rc == -EALREADY)
                                rc = 0;
@@ -4377,6 +4394,7 @@ void bnxt_ethtool_free(struct bnxt *bp)
 }
 
 const struct ethtool_ops bnxt_ethtool_ops = {
+       .cap_link_lanes_supported       = 1,
        .supported_coalesce_params = ETHTOOL_COALESCE_USECS |
                                     ETHTOOL_COALESCE_MAX_FRAMES |
                                     ETHTOOL_COALESCE_USECS_IRQ |